Fix GN toolchains to use proper out dir.

components/variations/BUILD.gn

Index: components/variations/BUILD.gn
diff --git a/components/variations/BUILD.gn b/components/variations/BUILD.gn
index 53384c3c67327dc4bf59ddba00a4a3d07ce7ce0b..da9ef09ab6755f17b20667f2f18bf59484d1d6f5 100644
--- a/components/variations/BUILD.gn
+++ b/components/variations/BUILD.gn
@@ -2,6 +2,10 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+if (is_android) {
+  import("//build/config/android/rules.gni")
+}
+
 static_library("variations") {
   sources = [
     "active_field_trials.cc",
@@ -41,4 +45,17 @@ static_library("variations") {
     "//components/variations/proto",
     "//third_party/mt19937ar",
   ]
+
+  if (is_android) {
+    deps += [ ":jni" ]
+  }
+}
+
+if (is_android) {
+  generate_jni("jni") {
+    sources = [
+      "android/java/src/org/chromium/components/variations/VariationsAssociatedData.java",
+    ]
+    jni_package = "variations"
+  }
 }